Generally, homicide is the causing of death of another person (s.222(1)), irrespective of whether there was any intention to cause death or if it was by accident. There is culpable homicide and non-culpable homicide.(s. 222(2)).

Culpable homicide refers to the types of homicide for which there are criminal penalties. It includes causing death (s.222(5)):

by means of an unlawful act,

by criminal negligence,

by causing that human being, by threats or fear of violence or by deception, to do anything that causes his death, or

by wilfully frightening that human being, in the case of a child or sick person.

These methods are all categorized as either murder, manslaughter, or infanticide.(s.222(4))

(ii) means to cause him bodily harm that he knows is likely to cause his death, and is reckless whether death ensues or not;

(b) where a person, meaning to cause death to a human being or meaning to cause him bodily harm that he knows is likely to cause his death, and being reckless whether death ensues or not, by accident or mistake causes death to another human being, notwithstanding that he does not mean to cause death or bodily harm to that human being; or

(c) where a person, for an unlawful object, does anything that he knows or ought to know is likely to cause death, and thereby causes death to a human being, notwithstanding that he desires to effect his object without causing death or bodily harm to any human being.

R.S., c. C-34, s. 212.

...

Classification of murder
231. (1) Murder is first degree murder or second degree murder.

Planned and deliberate murder
(2) Murder is first degree murder when it is planned and deliberate.

...

Second degree murder
(7) All murder that is not first degree murder is second degree murder.

Murder reduced to manslaughter
232. (1) Culpable homicide that otherwise would be murder may be reduced to manslaughter if the person who committed it did so in the heat of passion caused by sudden provocation.What is provocation
(2) A wrongful act or an insult that is of such a nature as to be sufficient to deprive an ordinary person of the power of self-control is provocation for the purposes of this section if the accused acted on it on the sudden and before there was time for his passion to cool.Questions of fact

(3) For the purposes of this section, the questions

(a) whether a particular wrongful act or insult amounted to provocation, and

(b) whether the accused was deprived of the power of self-control by the provocation that he alleges he received,

are questions of fact, but no one shall be deemed to have given provocation to another by doing anything that he had a legal right to do, or by doing anything that the accused incited him to do in order to provide the accused with an excuse for causing death or bodily harm to any human being.
...Manslaughter
234. Culpable homicide that is not murder or infanticide is manslaughter.
R.S., c. C-34, s. 217.
...Manslaughter
236. Every person who commits manslaughter is guilty of an indictable offence and liable

(a) where a firearm is used in the commission of the offence, to imprisonment for life and to a minimum punishment of imprisonment for a term of four years; and

Proof of the element of "planned and deliberate", or any of the specific elements of 231(3),(4),(5),(6.01),(6.1), and (6.2), are necessary to make out first degree murder. Without this element, second degree murder is made out.

First degree and second degree murder are not separate offences. Section 231, defining first degree murder, is "purely a classification section and does not create a separate substantive offence." The distinction is only for the purpose of sentencing.[1]

Both types of murder requires one of three categories of requisite intent set out in s.229:

accused causes death and "means to cause death"; (s. 229(a)(i))

the accused causes death and "means to cause him bodily harm that he knows is likely to cause his death, and is reckless whether death ensues or not". (s. 229(a)(ii))

the accused causes death but does so by accident or mistake, while at some point during the act forms a meaning set out above in 229(a)(i) or 229(a)(ii). (s.229(b))

causes death while pursuing an "unlawful object" that "he knows or ought to know is likely to cause death". (s.229(c))

The necessary intent for murder requires proving a subjective foresight of death.[1]

The requisite intent does not need to be simultaneous to the act that causes death. The two must coincide with the "transaction" that forms the substance of the killing. The intent does not need to be present throughout the acts or series of actions or events. [2]

An accused may still be convicted if he does not know the victim's identity[3] or is mistaken as to the victim's identity.[4]

However, it can be "simple and need not necessarily be in place for a long period of time"[5]

A "deliberate" murder is not impulsive. It must be a considered act[6] where "he thinks about the consequences and carefully thinks out the act, rather than proceeding hastily, rashly or impulsively"[7]

The elements of "planned and deliberate" can be proven on by circumstantial evidence.[8] However, it cannot be equivocal or speculative of whether it was "planned and deliberate".[9]

There does not need to be care consideration of acts. Planning and deliberation can be made out by evidence of even a brief moment of consideration before the act.[10]

s. 231.
...Murder of peace officer, etc.
(4) Irrespective of whether a murder is planned and deliberate on the part of any person, murder is first degree murder when the victim is

(a) a police officer, police constable, constable, sheriff, deputy sheriff, sheriff’s officer or other person employed for the preservation and maintenance of the public peace, acting in the course of his duties;

(b) a warden, deputy warden, instructor, keeper, jailer, guard or other officer or a permanent employee of a prison, acting in the course of his duties; or

(c) a person working in a prison with the permission of the prison authorities and acting in the course of his work therein.

231.
...Hijacking, sexual assault or kidnapping
(5) Irrespective of whether a murder is planned and deliberate on the part of any person, murder is first degree murder in respect of a person when the death is caused by that person while committing or attempting to commit an offence under one of the following sections:

(a) section 76 (hijacking an aircraft);

(b) section 271 (sexual assault);

(c) section 272 (sexual assault with a weapon, threats to a third party or causing bodily harm);

Criminal harassment
(6) Irrespective of whether a murder is planned and deliberate on the part of any person, murder is first degree murder when the death is caused by that person while committing or attempting to commit an offence under section 264 and the person committing that offence intended to cause the person murdered to fear for the safety of the person murdered or the safety of anyone known to the person murdered.

Murder — terrorist activity
(6.01) Irrespective of whether a murder is planned and deliberate on the part of a person, murder is first degree murder when the death is caused by that person while committing or attempting to commit an indictable offence under this or any other Act of Parliament if the act or omission constituting the offence also constitutes a terrorist activity.

231.
...Murder — criminal organization
(6.1) Irrespective of whether a murder is planned and deliberate on the part of a person, murder is first degree murder when

(a) the death is caused by that person for the benefit of, at the direction of or in association with a criminal organization; or

(b) the death is caused by that person while committing or attempting to commit an indictable offence under this or any other Act of Parliament for the benefit of, at the direction of or in association with a criminal organization.

231.
...Intimidation
(6.2) Irrespective of whether a murder is planned and deliberate on the part of a person, murder is first degree murder when the death is caused by that person while committing or attempting to commit an offence under section 423.1.

Death occurs once the vital functions and organs irreversibly cease to operate.[1]

The Crown must prove as an essential element that the victim is dead. In most cases this is a trivial fact. It is only in murder cases with a missing body that there may be an issue in proving the element.[2]